Antiferroelectric, Chalcogen, Nonmetal, Phonons, Trigonal

• Bi-Fe-O
• Bi-Na-O-Ti
• Ba-O-Ti
• B-Fe-Gd-O
• Bi-Fe-O-Y
• Raman spectra
• wavenumber of optical phonon
• infrared spectra
• wavenumber of longitudinal optical phonon
• energy of optical phonon
• nonmetal
• chalcogen
• antiferroelectric
• ferroelectric
• transitional